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Chinese Physics B 2022年第2期31卷 109-118页

作者： Fei Yu Zinan Zhang Hui Shen Yuanyuan Huang Shuo Cai sichun du School of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha 410114China College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China

A memristive Hopfield neural network(MHNN)with a special activation gradient is proposed by adding a suitable memristor to the Hopfield neural network(HNN)with a special activation *** MHNN is simulated and dynamically analyzed,and implemented on ***,a new pseudo-random number generator(PRNG)based on MHNN is *** post-processing unit of the PRNG is composed of nonlinear post-processor and XOR calculator,which effectively ensures the randomness of *** experiments in this paper comply with the IEEE 754-1985 high precision32-bit floating point standard and are done on the Vivado design tool using a Xilinx XC7 Z020 CLG400-2 FPGA chip and the Verilog-HDL hardware programming *** random sequence generated by the PRNG proposed in this paper has passed the NIST SP800-22 test suite and security analysis,proving its randomness and high ***,an image encryption system based on PRNG is proposed and implemented on FPGA,which proves the value of the image encryption system in the field of data encryption connected to the Internet of Things(Io T).

关键词： memristive Hopfield neural network(MHNN) pseudo-random number generator(PRNG) FPGA image encryption decryption system

复值Hopfield神经网络的信号盲检测一步计算电路

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电子与信息学报 2024年第11期46卷 4123-4131页

作者：洪庆辉孙辰肖平旦韦正苗杜四春湖南大学信息科学与工程学院长沙410082

信号盲检测在大规模通信网络中具有重要的意义并得到了广泛的应用,如何快速得到信号盲检测结果是新一代实时通信网络的迫切需求。为此,该文从模拟电路的角度设计了一种能加速信号盲检测的复值Hopfield神经网络(CHNN)电路,该电路可一步... 详细信息

信号盲检测在大规模通信网络中具有重要的意义并得到了广泛的应用,如何快速得到信号盲检测结果是新一代实时通信网络的迫切需求。为此,该文从模拟电路的角度设计了一种能加速信号盲检测的复值Hopfield神经网络(CHNN)电路,该电路可一步完成大规模并行计算,提高信号盲检测速度,同时该电路可以通过调整忆阻器的电导和输入电压来实现可编程功能。Pspice仿真结果表明,该电路的计算精度可达99%以上,运行时间比Matlab软件仿真快3个数量级,此外,该电路具有良好的鲁棒性,即使在20%的噪声干扰下,仍能保持99%以上的计算精度。

关键词：电路设计忆阻器复值Hopfield神经网络信号盲检测

基于忆阻器的可编程矩阵行列式求解电路设计及应用

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中国科学：信息科学 2023年第5期53卷 1008-1025页

作者：肖平旦洪庆辉杜四春孙辰黎俊张吉良湖南大学物理与微电子科学学院长沙410082 湖南大学信息科学与工程学院长沙410082 湖南大学半导体学院(集成电路学院) 长沙410082

矩阵行列式的求解在工程应用中具有重要的意义并得到了广泛的应用,如何高效快速地求解矩阵行列式成为物联网大数据时代的迫切需求.为此,本文提出了一种基于忆阻器的可编程模拟电路,可一步完成任意阶行列式的计算.首先,本工作给出了二阶... 详细信息

矩阵行列式的求解在工程应用中具有重要的意义并得到了广泛的应用,如何高效快速地求解矩阵行列式成为物联网大数据时代的迫切需求.为此,本文提出了一种基于忆阻器的可编程模拟电路,可一步完成任意阶行列式的计算.首先,本工作给出了二阶行列式和三阶行列式的计算电路.在此基础上,通过组合电路的方式得到任意阶数行列式求解电路.同时,该电路还可以通过调节忆阻器的电导和输入电压源来实现可编程的功能. PSPICE的仿真结果表明,该电路的精度在99.4%以上,运行时间比MATLAB仿真快3个数量级,即便在10.0%的误差干扰的情况下,其精度仍能超过93%.相比于数字处理器,该电路在面积开销与功耗上具有显著优势.最后,该电路可通过各个卫星的余弦参数来计算多卫星构成的空间矩阵行列式以辅助定位卫星组合的选择,其计算结果的平均精度可达99.7%.

关键词：忆阻器电路设计可编程行列式卫星定位

基于复数域上的网络编码的MIMO系统预编码器设计

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计算机应用研究 2016年第7期33卷 2135-2138页

作者：杜四春章彬雷友诚银红霞湖南大学信息科学与工程学院长沙410082 湖南大学电气与信息工程学院长沙410082

针对复数域网络编码中复数θ的选取以及中继和目的节点处如何有效检测原始数据的问题,提出一种收发联合优化的预编码方案。设计一种等相位预编码器选取编码复数θ以降低数据传输过程中的误码率,提出一种迭代预均衡算法在中继和目的节点... 详细信息

针对复数域网络编码中复数θ的选取以及中继和目的节点处如何有效检测原始数据的问题,提出一种收发联合优化的预编码方案。设计一种等相位预编码器选取编码复数θ以降低数据传输过程中的误码率,提出一种迭代预均衡算法在中继和目的节点处检测和恢复原始数据,在提高系统信道容量的同时改善整个系统的抗干扰能力。仿真结果显示,该方案相对现有复数域网络编码方案能够获得更低的误码率,且在无信道状态信息的情况下也能获得较线性预均衡方案更低的误码率以及更高的信道容量。

关键词：复数域网络编码收发联合优化预编码误码率

Towards gauge unified,supersymmetric hidden strong dynamics

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Chinese Physics C 2021年第1期45卷 16-31页

作者： Cheng-Wei Chiang sichun Sun Fang Ye Department of Physics NTUTaipei Department of Physics and Center for Mathematics and Theoretical Physics NCUTaoyuan Institute of Physics Academia SinicaTaipei Physics Division NCTSHsinchu Institute for Advanced Study The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong

We consider a class of models with extra complex scalars that are charged under both the Standard Model and a hidden strongly coupled S U(N)h gauge sector and discuss the seenarios in which the new scalars are identified as the messenger fields that mediate the spontaneously broken supersymmetries from the hidden sector to the visible *** new scalars are embedded into 5-plets and 10-plets of an S(/(5)v gauge group that potentially unifies the Standard Model gauge *** Higgs bosons remain as elementary *** the supersymmetrized version of this class of models,vector-like fermions whose left-handed components are superpartners of the new scalars are *** to the hidden strong force,the new low-energy scalars hadronize before decaying and thus evade the common direct searches of the supersymmetric *** can be seen as a gauge mediation seenario with the scalar messenger fields forming low-energy bound *** also discuss the possibility that in the tower of bound states formed under hidden strong dynamics(of at least the TeV scale),there exist a dark matter candidate and the collider signatures(***,diboson,or dijet)of models that may show up in the near future.

关键词： collider searches beyond the standard model extra complex scalars

Reveal heterogeneous motion states in single nanoparticle trajectory using its own history

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Science China Chemistry 2021年第2期64卷 302-312页

作者： Hansen Zhao Feng Ge sichun Zhang Xinrong Zhang Yan He Department of Chemistry Tsinghua UniversityBeijing100084China

Single particle tracking(SPT)has long been utilized for investigation of complex system dynamics such as nanoparticle-cell interaction,however,the analysis of individual particle motions is always a difficult *** methods treat each data point or fragment on the recorded trajectory as an isolated"atom"and determine their relationship based on externally predefined models or physical states,which inevitably lead to oversimplification of the associated spatiotemporal ***,inspired by the historical analysis in social science,we propose a modeless preprocessing framework for SPT analysis based on the"history"of the *** new strategy consists of 3 steps:(1)assign a"history"to each data point and construct successive overlapped historical vectors;(2)perform unsupervised clustering in the vector space to find their relative differences;(3)project differences back to the trajectory by coloring each point accordingly for *** a result,the inner heterogeneity of the particle motion self-emerges as a colored trajectory,exhibiting a global picture of the local state transitions and providing valuable information for further model-based *** the complexity issues at various spatiotemporal scales have attracted increasing attention,and individual objects such as single molecules,cells,vehicles and even stars in the universe could all be treated as"single particles",this presuppositionless data preprocessing approach could help the investigations of many complex systems in fundamental research.

关键词： single particle tracking nanoparticle machine learning

Algorithms and statistical analysis for linear structured weighted total least squares problem

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Geodesy and Geodynamics 2024年第2期15卷 177-188页

作者： Jian Xie Tianwei Qiu Cui Zhou Dongfang Lin sichun Long School of Earth Science and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China College of Science Central South University of Forestry and TechnologyChangsha 410018China National-Local Joint Engineering Laboratory of Geo-spatial Information Technology Hunan University of Science and TechnologyXiangtan 411201China

Weighted total least squares(WTLS)have been regarded as the standard tool for the errors-in-variables(EIV)model in which all the elements in the observation vector and the coefficient matrix are contaminated with random ***,in many geodetic applications,some elements are error-free and some random observations appear repeatedly in different positions in the augmented coefficient *** is called the linear structured EIV(LSEIV)*** kinds of methods are proposed for the LSEIV model from functional and stochastic *** the one hand,the functional part of the LSEIV model is modified into the errors-in-observations(EIO)*** the other hand,the stochastic model is modified by applying the Moore-Penrose inverse of the cofactor *** algorithms are derived through the Lagrange multipliers method and linear *** estimation principles and iterative formula of the parameters are proven to be *** first-order approximate variance-covariance matrix(VCM)of the parameters is also derived.A numerical example is given to compare the performances of our proposed three algorithms with the STLS ***,the least squares(LS),total least squares(TLS)and linear structured weighted total least squares(LSWTLS)solutions are compared and the accuracy evaluation formula is proven to be feasible and ***,the LSWTLS is applied to the field of deformation analysis,which yields a better result than the traditional LS and TLS estimations.

关键词： Linear structured weighted total least squares Errors-in-variables Errors-in-observations Functional modelmodification Stochastic model modification Accuracyevaluation

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面向工业品缺陷检测的对比表示学习

计算机科学 2025年第1期52卷 210-220页

作者：罗航宇王小平梅萌赵文豪刘思纯同济大学电子与信息工程学院上海200092

在大规模制造业中,缺陷检测旨在发现有缺陷的零部件,如损坏、错位的和存在印刷错误的部件等。由于缺陷类型未知以及缺陷样本短缺,工业品缺陷检测面临着极大的挑战。为克服上述困难,一些方法利用来自自然图像数据集的通用视觉表示,提取... 详细信息

在大规模制造业中,缺陷检测旨在发现有缺陷的零部件,如损坏、错位的和存在印刷错误的部件等。由于缺陷类型未知以及缺陷样本短缺,工业品缺陷检测面临着极大的挑战。为克服上述困难,一些方法利用来自自然图像数据集的通用视觉表示,提取广义特征来进行缺陷检测。然而,提取到的预训练特征与目标数据之间存在分布差异,直接使用该特征会导致检测性能不佳。因此,提出了一种基于对比表示学习的方法ConPatch。该方法采用对比表示学习来收集相似特征或者分离不相似特征,从而学习面向目标的特征表示。为了解决缺乏缺陷标注的问题,将数据表示之间的两种相似性度量即成对相似度和全局相似度作为伪标签。此外,采用了轻量化的内存库,仅将全部正常样本即全部无缺陷样本的特征中心存储到内存库中,从而减小了空间复杂度和内存库的尺寸。最后,将正常特征拉近至一个超球面内,而缺陷特征则分布在超球面外,以此来聚集正常特征。实验结果显示,在工业品缺陷检测数据集MVTec AD中,基于Wide-ResNet50的ConPatch模型的I-AUROC和P-AUROC分别达到99.35%和98.26%。在VisA数据集中,ConPatch模型的I-AUROC和P-AUROC分别达到95.50%和98.21%。上述结果验证了模型的有效性。

关键词：工业品缺陷检测对比表示学习相似性度量内存库超球面

Cloning and expression of the nuclear transcription factor SIβFTZ-F1 cDNA from Spodoptera fitura

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Insect Science 2011年第6期18卷 635-644页

作者： Lin Tang Chun Zhang Lin Liu Qili Feng sichun Zheng Guangdong Provincial Key Laboratory of Biotechnology for Plant Development School of Life Sciences South China Normal University Guangzhou College of Life Sciences Hunan University of Arts and Sciences Changde Hunan Province China

Insect molting and metamorphosis are regulated by 20-hydroxyecdysone, which activates the ecdysone receptors, followed by expression of a series of transcription factors. Beta Fushi Tarazu-Factor 1 （βFTZ-F1） is one of these ecdysis-related earlyexpressed transcription factors. A βFTZ-F1 complementary DNA （cDNA） was cloned from Spodoptera litura. The full-length cDNA was 2 194 bp in length and the open reading frame ofS1βFTZ-F1 cDNA consisted of 1 659 bp and encoded a 552-amino acid protein with a molecular mass of 61.4 kDa. Homology analysis revealed that S1βFTZ-F 1 protein shared high identities to its homologues from other species. The A/B domains and the D domains were diverse among the insectβFTZ-F 1 proteins, but DNA binding domains （C domain） and the ligand binding domains （E domain） were highly conserved. Northern blot analysis detected a transcript of 2.2 kb in the epidermis of fifth to sixth molting larvae. Reverse transcription polymerase chain reaction revealed that SIβFTZ-F1 gene started to increasingly and periodically express before each molt, followed by a decrease during the intermolt stages.

关键词： ecdysis metamorphosis molt Spodoptera litura transcription factor

CO_(2) capture by double metal modified CaO-based sorbents from pyrolysis gases

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Chinese Journal of Chemical Engineering 2022年第3期35卷 40-49页

作者： Xiaobin Chen Yuting Tang Chuncheng Ke Chaoyue Zhang sichun Ding Xiaoqian Ma School of Electric Power South China University of TechnologyGuangzhou 510640China Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization Guangzhou 510640China

High-temperature pyrolysis technology can effectively solve the problem of municipal solid waste ***,the pyrolysis gas contains a large amount of CO_(2),which would adversely affect the subsequent *** address this problem,a novel method of co-precipitation modification with Ca,Mg and Zr metals was proposed to improve the CO_(2)capture performance.X-ray diffraction(XRD)patterns and energy dispersive X-ray spectroscopy analysis showed that the two inert supports MgO and CaZrO_(3)were uniformly distributed in the modified calcium-based *** addition,the XRD results indicated that CaZrO_(3)was produced by the reaction of ZrO_(2)and CaO at high *** effects of doping ratios,adsorption temperature,calcination temperature,CO_(2)concentration and calcination atmosphere on the adsorption capacity and cycle stability of the modified calcium-based sorbent were *** modified calcium-based sorbent achieved the best CO_(2)capture performance when the doping ratio was 10:1:1 with carbonation at 700℃ under 20%CO_(2)/80%N_(2)atmosphere and calcination at 900℃ under100%N_(2)*** ten cycles,the average carbonation conversion rate of Ca-10 sorbent was 72%.Finally,the modified calcium-based sorbents successfully reduced the CO_(2)concentration of the pyrolysis gas from 37%to 5%.

关键词： Pyrolysis gas CO_(2)capture Co-precipitation CaO-based sorbents Modified sorbents